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What is everyones opinion on doing a transmission flush. I want to change my trans. oil to schaeffer's at 50,000 miles. I have heard both good and bad about the flush. Also how is it done on the new 68rfe since there are no couplers at the cooler for the lines. Any opinions on what/how to do it are welcome also.
 

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I have my transmission flushed by my dealer. He will service it either way (drain or flush). Before servicing the transmission for the first time I e-mailed another dealer regarding servicing and I was given two prices, drain and flush. I do not know where they open the line. I put 130 - 140 thousand miles on my truck per year and I prefer flushing. On my previous truck ('99 Ford) I drained and changed the filter for the first couple hundred thousand miles but converted to flushing when the pan threads wore out. I Put over 600,000 miles on that truck without any transmission problems. Also my fellow drivers preferred flushing.
 

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It seems the only bad stories come from those that trans were tired already .
But I still recomend dropping the pan , this give you a chance to see whats going on in the trans [ stuff in pan ] and adjust bands / pressures , filter goes both ways , the flushing is spoused to flush out the filter , this is an other chance to create issues , by particals going back into trans , so replace filter , then flush .
Also just dropping pan , only changes about 1/4-1/3 of the fluid , flushing changes all .
 

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"Trans flush" means different things to different people.

The horror stories are mostly from trans flushes where they hook the transmission up to a machine that drains it out of fluid, puts some solvent through it, and then fills it up with new fluid.

But to get a certain breed of oil out and replace it with a new breed of oil, you just need to do the hill billy "trans flush", which involves draining the pan, reinstalling the pan and filling it with new ATF, and then disconnecting the transmission oil input line.

You run the tranny in neutral for a minute or so with the ATD input line disconnected, pouring new fluid into the dipstick in the process. You might need to do this in three or four steps to let the new ATF flow into the pan fast enough.

The idea being that the transmission will pump all the old fluid out of that input line, replacing it with new fluid.

You should have a gallon or so that you need to pump out through the input line.
 

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Heres the low down on why you have heard its bad to do a tranny flush. There are people that wait to flush after a ton of miles, it could be different for each truck depending on driving habits, this could happen at 75k, 100k, or more. But as the oil gets older and burnt it becomes thicker. The seals and orings become worn, at a faster rate than if you did a flush at the recommended miles. With the worn seals and orings, it will seal just fine with the thicker older oil in the tranny. if you flush it and put new thinner oil in the seals and other parts will tend to leak and not function correctly and will result in transmission failure. So if all you did was drop the pan to change the filter and the small bit of oil that drained during this process you would be fine rather than doing a true flush.

But if you do a tranny flush from the dealer at the recommended miles you will not have any problems at all you and you will be doing the tranny a favor.

Also dont use any thing else in that tranny other than what dodge puts in it. Those clutches in there are designed for that oil along with everything else. I found this out the hard way. I did not start having problems with my 48RE until i changed it to Amsoil ATF, I could not figure out why it was acting up until i talked to the dealer about it. But it did not matter after that because i got the good dodge oil in there and then pulled a 10k trailer through the hills with a 120hp module on the truck and i really screwed up the tranny.
 
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